Chantel Lenard, executive director of U.S. marketing and a 25-year company veteran, is leaving June 1 to "pursue other interests," said Marisa Bradley, a Ford spokeswoman. Lenard is being replaced by Andrew Frick, currently director of sales and service at Ford's Lincoln luxury line, Bradley said. The move was announced internally at Ford on Monday, Bradley said.

The departure comes as Ford's board of directors ups the pressure on CEO Mark Fields to better explain the company's fading fortunes and his plan to turn things around.

Her departure is unrelated to any operational issues at the company and was of her own choosing, Bradley said.

"Chantel Lenard has elected to leave the company after 25 years," Bradley said in an emailed statement. "We thank her for her many years of service and wish her all the best going forward."

As Ford focuses on developing driverless cars and robo-taxis, its traditional business has struggled more than crosstown rival General Motors Co. in a slowing U.S. auto market. Ford's first quarter adjusted earnings fell 42 percent, while GM appears on pace for another record annual profit. Ford's U.S. market share fell to 15.1 percent in the first four months of the year, from 15.6 percent during the same period last year, according to AutoData Corp.

Neither Lenard nor Frick was available for interviews, Bradley said. Frick is being replaced at Lincoln by Greg Wood, currently regional manager of sales and service for Ford in Dallas.